WASHINGTON -- Two leading national security picks for Donald Trump’s incoming administration warned that Russia is seeking to disrupt U.S. and European institutions and advocated an aggressive military and intelligence approach to counter Moscow.

The comments by James Mattis and Mike Pompeo, Trump’s picks to run the Pentagon and the CIA, respectively, contrast with the more conciliatory rhetoric toward Moscow that the Republican president-elect voiced throughout his campaign and after his election on November 8.

The two nominees spoke at separate Senate confirmation hearings on January 12, with both characterizing Russia as an aggressive actor that must be met with staunch U.S. resistance on the international stage.

Mattis, a former Marine Corps general, told the Senate Armed Services Committee that Russian President Vladimir Putin is seeking to break up the NATO alliance and that Washington must confront Russian behavior.

Saying Russia has chosen to become a "strategic competitor," Mattis, 66, told lawmakers that he does not oppose cooperation with Moscow but that the United States must remain clear-eyed about its intentions and actions.

Asked about the main threats to U.S. interests, he said: "I would consider the principal threats to start with Russia."

"I’m all for engagement, but we also have to recognize reality and what Russia is up to," added Mattis, who led Marine divisions in the invasion of Afghanistan in 2001 and the 2003 invasion to topple Iraq's Saddam Hussein.

“There are a decreasing number of areas where we can engage cooperatively and an increasing number of areas where we are going to have to confront Russia,” he said.

Citing his recent visit to the three Baltic states -- NATO members that were under Moscow’s domain during Soviet times -- Senator John McCain (Republican-Arizona) said during the hearing that leaders there had pressed him to back a permanent U.S. military presence in the region.

A U.S. rotating force began deploying in Eastern Europe in January under a program known as the European Reassurance Initiative launched in conjunction with NATO’s response to Russia’s 2014 annexation of Ukraine’s Crimean Peninsula.

Asked by McCain whether Mattis supports a permanent U.S. military presence in the three countries -- Estonia, Lithuania, and Latvia -- the retired general said he does.

After serving in Iraq and Afghanistan, Mattis, 66, became head of U.S. Central Command in 2010, overseeing military operations in the Middle East until his retirement in 2013.

Since retiring, he has been outspoken in his criticism of President Barack Obama's policies in the region, saying they have contributed to the rise of extremism there.

He's also voiced tough positions on Iran, as well as Russia, something that puts him at odds with the conciliatory stance Trump has expressed toward Moscow.

Asked by lawmakers about the landmark deal that curtailed Iran’s nuclear ambitions in exchange for lifting crippling sanctions, Mattis criticized the agreement.

"Sir, I would not have signed it," he said.

During his election campaign, Trump drew fire from both Republicans and Democrats for questioning the U.S. commitment to NATO members who don’t maintain sufficient defense spending. He has since voiced greater support for the alliance, saying it has boosted its counterterrorism efforts.

Meanwhile, Pompeo told the Senate Intelligence Committee on January 12 that Russia "has reasserted itself, aggressively invading and occupying Ukraine, threatening Europe, and doing nothing to aid in the destruction and defeat" of Islamic State (IS) militants.

Trump’s nomination of Pompeo, a Republican from Kansas in the U.S. House of Representatives, comes amid a mounting furor over Russia’s alleged attempts to help Trump defeat Democratic rival Hillary Clinton in the November 8 election.

The U.S. intelligence community accuses Putin of ordering the hacking campaign, which included the theft and publishing of Democratic e-mails seen as damaging Clinton in the election.

Trump, who says he wants to improve ties with Moscow, has publicly questioned the intelligence findings, though on January 11 he acknowledged that Russia was likely behind the cyberattacks. He insists that the hacking had no impact on the outcome of the election.

In his testimony, Pompeo firmly backed the U.S. intelligence conclusions about Russian involvement, saying he attended last week's meeting at which top U.S. officials briefed Trump about their classified report on the matter.

"With respect to this report in particular, it's pretty clear about what took place here -- about Russian involvement in efforts to hack information and to have an impact on American democracy," Pompeo, 53, said.
He called the cybercampaign "an aggressive action taken by the senior leadership inside of Russia."

Russia has repeatedly denied any involvement in the hacks targeting Clinton’s campaign and other U.S. political organizations and personalities.

Mattis's nomination as defense secretary had attracted concern among some members in Congress, due to a U.S. law barring military officers from becoming the civilian head of the Defense Department within seven years of retiring from the military.

The nearly 70-year-old law was passed to ensure U.S. armed forces remained under civilian, rather than military, leadership.

The Senate committee ultimately voted 24-3 for a one-time exemption to the law.

Later on January 12, the Republican-led House Armed Services Committee voted 34-28 to grant Mattis the exemption.

Congress passed such a waiver only once before, for Army General George Marshall in 1950.